All of the downsides you mention are not that bad in my opinion.
I don't feel bad that people buy a legacy. I believe that a legacy of being a massive philanthropist is a legacy worth having.
I don't feel bad that they "erase their past", because all people can still be judged by the totality of their actions.
The recognition does benefit the people that make the donations. Doesn't seem to be a problem to me.
Charitable organizations are dependent upon the whim of their donors regardless of whether the donors get any recognition.
The fraction of non-profit budgets that are spent on awareness seems to be a tangential point that I do not understand.